Pattern
Pattern. (2) A collectors' term for a wide number of early strikes, as die trials, hub trials, die adjustment strikes, experimental pieces, other trial pieces; anything that is different from the production run pieces that are not mint errors. French coins have essai on pattern coins for sale to the public; the term translates "trial" and are usually struck on thick planchets (piedforts).
excerpted with permission from
An Encyclopedia of Coin and Medal Technology
For Artists, Makers, Collectors and Curators
COMPILED AND WRITTEN BY D. WAYNE JOHNSON